Sheet-metal pole.



PATENTED DEC. 10, 1907.

W. L. WRIGHT. SHEET METAL POLE.

APPLICATION FILED SEPT. 7, 1906.

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THE NORRIS pzrsns 0a., WISNINGTON. D c,

WILFRED L. WRIGHT, OF PHILADELPHIA, PENNSYLVANIA.

SHEET-METAL POLE.

Specification of Letters Patent.

Patented Dec. 10, 1907.

Application filed September '7. 1906. Serial No. 333.583-

To all whom it may concern:

Be it known that I, WILFRED L. WRIGHT, a citizen of the United States of America, and resident of Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Sheet-Metal Poles, of which thefollowing, taken in conjunction with the drawing, which forms a part hereof, is a full, clear, and concise specification.

My invention relates to sheet metal poles or posts of the kind in which the component sections are adapted to be wedged longitudinally, one within the other, to be held in such relation, either temporarily or permanently, by the frictional engagement of the two parts with each other, and my invention consists in the simplification of the sheet metal sections of such poles whereby they can bemanufactured on a practical basis, in satisfactory competition with wooden poles, and

whereby also the assembled pole will afford' the requisite strength with the least amount of material and work, all as will be hereinafter explained and more particularly pointed out in the accompanying claims.

In the drawings Fi ure 1 is a side elevation in perspective of a pode of my invention; Fig. 2 an enlarged transverse section of such pole; Fig. 3 a diagram of one of the blanks from which the pole sections are formed; and Fig. 4 a diagram illustrating the method of bending the pole sections.

Accordin to my invention the two sections of whlch the pole is made, are of sub stantially identical shape and formation, each being formed in similar manner from a flat sheet metal blank such as is shown in Fig. These blanks are preferably cut with a taper from end to end suited to the required taper of the finished pole, and have their opposite side margins first bent at substantially right angles to the body of the sheet as indicated by the dotted lines of Fig.

4, and then the sheet itself is bent or folded upon its central longitudinal aXis represented by the line a, a, so that the two halves assume an angle of substantially 90 degrees from each other and the marginal flanges 1 turn inwardly as indicated by the full lines of Fig. 4. These bending operations, three in number, complete the formation of each pole section, and by reason of the special disposition of the angles it is manifest that the said operations can be performed by running the blank through ordinary bending or flanging machinery of well understood construction, and that the necessity of specially shaped stamping dies such as heretofore required for tapered pole sections, is therefore avoided.

Being symmetrical in form, as well as identical in shape, the sections made as above described may be wedged one within the other indiscriminately, without requiring to be made in pairs; and the described arrangement of the marginal flanges and angles, moreover, facilitates the assembling of the two sections,which is accomplished by placing the smaller end of one section, such as A (indicated by dotted lines in Fig. 2) within'the base portion of the other, such as B, and then pushing it into the latter until it wedges.

The necessity of providing a careful registry of the meeting portions of the two sections or of smoothing or milling their edges is entirely obviated and the time and skill 're quired for assembling the pole sections is reduced to a minimum.

The pole as thus assembled is square in crosssection and the outsides of the corners 2 which are formed by the junction of the flanges with the halves of the inner section A are forced into frictional contact respectively with the insides of the corresponding corner portions of the outer section B; the

overlapping marginal portions of the two sections forming true lap joints which, being located at diametrically opposite corners of the pole and being formed around the angle of said corners, constitute a substantial stiffening reinforcement for the pole and offer the greatest resistance to the tendency of the sections to weave under the strains to which the .pole may be subjected.

The elasticity of the sections retains the members of the lapj-oints in binding contact, which will ordinarily be suflicient, but extra retaining means may be provided for this purpose if desired. For example, one or more yard-arm apertures 8 may be formed respectively in the sides of the sections A and B, so as to register'in the assembled pole, and the yard-arm inserted therethrough will serve to aid in retaining the sections in proper relation. Such apertures, however, do not require a diflerent treatment for the inner and outer sections, inasmuch as they are obviously made in the same relative location in each blank.

It will be understood that the pole is complete of two parts and does not require the use of hoops or headings or other special means for holding the sections a ainst lateral separation. The flanges 1 nee sufficient width to produce a clasping or interlocking engagement, which is very small when they are bent at right angles as described, and owing to the location of the lapjoints, it is obvious that variations in the width of the flanges will not affect the assemblage of the sections and that therefore the measurement of the blanks consists mainly in determining the three bending lines, which permits the device to be made by comparatively unskilled labor, Moreover it will be understood that my invention is not limited to poles of exactly the crosssectional shape shown in the drawings, but that other forms may be employed which.

will involve the arrangement of the sections as above described.

Havin described my invention, what I claim an desire to secure by Letters Patent is as follows:

1. A sheet metal pole comprised of two similar sheet metal sections respectively bent upon their central longitudinal axes and provided with inwardly bent marginal flanges, the said sections being adapted to be wedged one within the other, with the outsides of the marginal corner portions of the inner seconly be of tion respectively forced into frictional contact within the angles of the marginal flanges of the other section.

2.'A' sheet metal pole comprised of two similar and longitudinally tapered sheet metal sections bent at substantially ninety degrees along their central longitudinal axes and provide with mar inal side flanges-inwardly bent at substantially a rightangle on each side thereof, the said sections being adapted to be wed ed one within the other,

said sections bein located at diametrically opposite corners of the pole and constitutin lap-joints formed around the angles of said corners.

In testimony whereof, I have signed my name, to the specification in the presence of two subscribing witnesses.

WILFRED L. WRIGHT.

Witnesses:

H. GQKIMBALL, A. A. LORZER. 

